Pad structure for liquid crystal display and method of manufacturing thereof

ABSTRACT

A liquid crystal display has a pad structure. The pad structure includes at least one pad formed on a substrate, an insulating film formed on the pad, and at least one conductive layer connected to the pad through contact holes defined through the insulating film. The insulating film covers side surfaces of the pad and a portion of the substrate adjacent to the side surfaces of the pad.

This is a divisional application of U.S. patent application Ser. No.11/889,184, filed on Aug. 9, 2007 now U.S. Pat. No. 7,741,206, which isa divisional of application Ser. No. 09/894,874, filed Jun. 29, 2001,now U.S. Pat. No. 7,262,827, issued on Aug. 28, 2007, which claims thebenefit of Korean Patent Publication No. 2000 43184 filed on 26 Jul.2000, all of which are hereby incorporated by reference for all purposesas if fully set forth herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention generally relates to a display device and, moreparticularly, to pads for an LCD (Liquid Crystal Display) and amanufacturing method thereof.

2. Description of the Related Art

CRTs (Cathode Ray Tubes) have been the primary type of display devicefor instrumentation system monitors, information system terminals, andtelevisions. However, conventional CRTs have not been able to respond tothe need to manufacture electronic products with reduced size and weightbecause CRTs are fundamentally large and heavy.

LCDs (Liquid Crystal Displays), which are relatively thin and lightweight, have been developed to replace the conventional CRT. In recentyears, LCDs have begun to play an important role as a plat-type displaydevice, thereby increasing market demand for LCDs.

Generally, a low cost, high performance thin film transistor-LCD(TFT-LCD) employs a non-crystalline silicone thin film transistor as aswitching element. Currently, most LCD development is directed towardhigh resolution systems such as SVGA (800×600) and XVGA (1024×768) ascompared to VGA (Video Graphic Array; maximum resolution: 640×480pixels). Consequently, development and application of the TFT-LCDindustry have been accelerated due to increase in size and enhancementin resolution. As a result, there have been many attempts to increasemanufacturing productivity and decrease cost by simplifyingmanufacturing processes and improving manufacturing yield.

The LCD uses an electrooptical property of liquid crystals that areinjected into an inside of a panel. In contrast to a PDP (Plasma DisplayPanel), a FED (Field Emission Display), etc., the LCD can not emit lightitself. Hence, an LCD is provided with a back light as a separate lightsource to evenly emit light onto a display surface, thereby displaying apicture on the LCD panel.

Conventional LCD pads will now be explained with reference to FIGS. 1and 2. FIG. 1 is a sectional view of a gate pad of the conventional LCD,and FIG. 2 is a sectional view of a conventional data pad.

As shown in FIG. 1, the conventional gate pad comprise three areas: apad contact area I, a grinding area II, and an ACF (AnisotropicConductive Film) deposit area III. A pattern on the grinding area II isremoved before the ACF is deposited. The pad contact area I is incontact with the grinding area II at one side and extends beyond the ACFdeposit area III at another side. As such, the gate pad comprises a gatemetal 13 formed on a substrate 11; a protective film 17 and a gateinsulating film 15 having a plurality of contact holes thereon throughwhich a portion of the surface of the gate metal 13 is selectivelyexposed, and being sequentially laminated on an upper part of the gatemetal 13; a transparent metal layer 19 connected to the gate metal 13through the contact holes; an ACF 21 formed on an upper part of thetransparent metal layer 19 in the ACF deposit area III; and a tapecarrier package (TCP) layer 23 formed on the ACF 21.

Here, the transparent metal layer 19 is made of a layer of a transparentconductive material, such as ITO (Indium Tin Oxide), for use as a pixelelectrode of an active region. Accordingly, a gate signal can beinputted from the TCP layer 23 to be transmitted to the gate metal 13through the ACF 21 and through the transparent metal layer 19 and thentransmitted to a thin film transistor (not shown) disposed within theactive region.

The transparent metal layer 19 is formed in the pad contact area I suchthat most portions of the transparent metal layer 19 are covered by theACF 21. However, a portion F1 of the transparent metal layer 19 at aside of the active region is not covered by the ACF 21 and is exposed.Further, some parts of the contact holes, which serve as a passagewayfor transmitting the gate signal inputted from the TCP layer 23 to thegate metal 13, exist beyond the ACF deposit area III.

Furthermore, before the ACF 21 is deposited, the gate metal 13, the gateinsulating film 15, the protective film 17 and the transparent metallayer 19 in the grinding area II are removed. When the grinding processis completed, there is formed a portion F2 in which sectional surfacesof the gate metal 13 and the transparent metal layer 19 are exposed toambient air.

The LCD of FIG. 1 further shows a color filter substrate 32 facing thesubstrate 11, and a sealing compound 30 for bonding the substrate 11 tothe color filter substrate 32.

As shown in FIG. 2, the structure of a data pad is similar to that ofthe gate pad with the exception that there is a different width of eachpattern and pitch between the patterns. Accordingly, the data pad alsocomprises a pad contact area I, an ACF deposit area III, and a grindingarea II. The pad contact area I contacts the grinding area II at oneside and extends beyond the ACF deposit area III at the other side at aside of an active region.

As such, the data pad comprises a substrate 11; a source/drain metal 16formed on an upper part of a gate insulating film 15; a protective film17, formed on an upper part of the source/drain metal 16, having aplurality of contact holes through which a surface of the source/drainmetal 16 is selectively exposed; a transparent metal layer 19, formed inthe pad contact area I, connected to the source/drain metal 16 throughthe contact holes; an ACF 21 formed in the ACF deposit area III; and aTCP layer 23 formed on an upper part of the ACF 21. Therefore, a datasignal inputted from the TCP layer 23 is transmitted to the source/drainmetal 16 through the ACF 21 and through the transparent metal layer 19,and then transmitted to a thin film transistor (not shown) within theactive region.

In the data pad, similarly to the gate pad, the transparent metal layer19 exists within the pad contact area I. Most portions of thetransparent metal layer 19 are covered by the ACF 21, but a portion F3existing beyond the ACF deposit area III is exposed. The source/drainmetal 16, the protective film 17 and the transparent metal layer 19 inthe grinding area II are sequentially removed. When the grinding processis completed, there exists a portion F4, in which sectional surfaces ofthe source/drain metal 16 and the transparent metal layers 19 areexposed.

The conventional LCD pads have a number of disadvantages. For example,conventional LCD pads are prone to atmospheric corrosion or electrolyticcorrosion.

If an electrical signal is applied to the gate pad to be operated, thesectional surfaces of the gate metal and the transparent metal layerexposed after the grinding process, or the portion of the transparentmetal layer uncovered by the ACF may raise an electrochemical reactionwhich increases the possibility of atmospheric corrosion or electrolyticcorrosion on a portion of the gate metal, thereby leading to damage ofthe gate pad. That is, the thin film transistor is damaged due to a fineelectrical shock generated during the electrochemical reaction, and theresistance of the gate wiring increases due to the atmospheric corrosionand the electrolytic corrosion of the gate metal.

If an electrical signal is applied to the data pad to be operated, anelectrochemical reaction may be induced in the sectional surfaces of thesource/drain metal and the transparent metal layer exposed after thegrinding process or the portion of the transparent metal layer uncoveredby the ACF which increases the possibility of atmospheric corrosion orelectrolytic corrosion on a portion of the source/drain metal, therebyleading to damage of the data pad. That is, the thin film transistor isdamaged due to a fine electrical shock generated during theelectrochemical reaction, and the resistance of the data wiringincreases due to the atmospheric corrosion and the electrolyticcorrosion of the source/drain metal.

SUMMARY OF THE INVENTION

Accordingly, the present invention is directed to a liquid crystaldisplay pad that substantially obviates one or more of the problems dueto limitations and disadvantages of the related art.

An object of the present invention is to provide an LCD (Liquid CrystalDisplay) pad and a manufacturing method thereof, which can preventproperties of an LCD from being deteriorated by using improved gate anddata pads sufficiently resistible against an electrolytic corrosion or acorrosion.

Additional features and advantages of the invention will be set forth inthe description that follows, and in part will be apparent from thedescription, or may be learned by practice of the invention. Theobjectives and other advantages of the invention will be realized andattained by the structure particularly pointed out in the writtendescription and claims hereof as well as the appended drawings.

To achieve these and other advantages and in accordance with the presentinvention, as embodies and broadly described, a pad structure for aliquid crystal display comprises a substrate; a plurality of gate padsand data pads formed on the substrate; an insulating film formed onsurfaces of the gate pads and data pads; a plurality of transparentconductive layers electrically connected to the gate pads and the datapads; and an anisotropic conductive film formed on the transparentconductive layers to cover entire upper and side surfaces of thetransparent conductive layer.

In another aspect, a pad structure for a liquid crystal display with agrinding area, a pad contact area and an anisotropic conductive filmdeposit area comprises a tape carrier package layer to receive a drivingsignal; an anisotropic conductive film formed on a lower portion of thetape carrier package layer and covering at least the pad contact area ofthe liquid crystal display; an insulating film defining a plurality ofcontact holes therethrough, the insulating film disposed on a lowerportion of the anisotropic conductive film in the pad contact area ofthe liquid crystal display; a plurality of gate and data pads; and atransparent conductive layer electrically connecting the gate and datapads to the anisotropic conductive film through the contact holes,wherein upper and side surfaces of the gate and data pads are completelycovered by the insulating film and the transparent conductive layer.

In another aspect, a method for manufacturing a liquid crystal displayhaving a pad structure comprises the steps of forming a plurality ofgate pads at predetermined portions on a substrate; forming aninsulating film to cover the gate pads; forming data pads on theinsulating film; forming a protective film to cover the data pads;exposing portions of the gate and data pads; forming a transparentconductive layer to be electrically connected to the exposed portions ofthe gate and data pads; and forming an anisotropic conductive film onthe transparent conductive layer to entirely cover upper and sidesurfaces of the transparent conductive layer.

In another aspect, a method for manufacturing a pad structure on aliquid crystal display with a grinding area and a pad contact areacomprises the steps of forming gate pads on a substrate separated by adistance from a grinding area defined on the substrate; forming a gateinsulating film on the substrate and the gate pads; forming data pads onthe gate insulating film separated by a distance from the grinding area;forming a protective film on the substrate and the data pads; forming atransparent conductive film to be connected to the gate pads and thedata pads in the pad contact area via contact holes defined in the gateinsulating film and the protective film; and forming an anisotropicconductive film on the transparent conductive film to entirely coverupper and side surfaces of the transparent conductive film.

In another aspect, a pad structure for a liquid crystal displaycomprises a substrate; at least one pad formed on the substrate; aninsulating film formed on the pad, the insulating film covering sidesurfaces of the pad and a portion of the substrate adjacent to the sidesurfaces of the pad; and at least one conductive layer connected to thepad through contact holes defined through the insulating film.

In another aspect, a liquid crystal display formed on a substratecomprises an active region defined at a first portion of the substrate;and a pad contact area defined on a second portion of the substrateadjacent to the active region wherein the pad contact area includes atleast one pad formed on the substrate, an insulating film formed on thepad, at least one conductive layer connected to the pad through contactholes defined through the insulating film such that the insulating filmcovers side surfaces of the pad and a portion of the substrate adjacentto the side surfaces of the pad.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory and areintended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this specification, illustrate embodiments of the invention andtogether with the description serve to explain the principles of theinvention. In the drawings:

FIG. 1 is a sectional view of a gate pad of a conventional LCD (LiquidCrystal Display);

FIG. 2 is a sectional view of a data pad of the conventional LCD;

FIG. 3 is a sectional view of a gate pad of an LCD in accordance withthe present invention;

FIGS. 4A through 4F are sectional views illustrating a process formanufacturing the gate pad of FIG. 3;

FIG. 5 is a sectional view of a data pad of an LCD in accordance withthe present invention; and

FIGS. 6A through 6F are sectional views illustrating a process formanufacturing the data pad of FIG. 5.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference will now be made in detail to the preferred embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings.

As will be explained in detail below, the gate and data pads andaccording to the present invention have contact holes formed within anACF deposit area to transmit a gate signal and a data signal inputtedfrom a TCP layer to a gate metal or a source/drain metal. Sectionalsurfaces of the transparent metal layer and the gate metal or thesource/drain metal layer are protected from being exposed to ambient airafter the grinding process, thereby preventing corrosion and/orelectrolytic corrosion of the source/drain metal, the gate metal, or thetransparent conductive layer.

Initially, a gate pad according to the present invention, as shown inFIG. 3 for example, is divided into an ACF (Anisotropic Conductive Film)deposit area III, a pad contact area I, and a grinding area II. Here,the pad contact area I is spaced from the grinding area II by apredetermined interval and the pad contact area exists within the ACFdeposit area. The pad contact area I transmits a gate signal inputtedthrough an ACF to a gate metal 43. The pad contact area I has aplurality of contact holes through which a surface of the gate metal 43is exposed and also has a transparent metal layer 49 connected to thegate metal 43 through the contact holes.

Referring to FIG. 3, the gate pad comprises a substrate 41 including anactive region, and a pad region being divided into the grinding area II,the pad contact area I and the ACF deposit area III; a first metal layer43 formed on the substrate in the pad contact area I and the activeregion; a gate insulating film 45 and a protective film 47 laminated onthe substrate including the first metal layer 43 and having theplurality of contact holes through which a surface of the first metallayer 43 is exposed within the pad contact area I; the transparent metallayer 49 electrically connected to the first metal layer 43 through thecontact holes and being formed within the pad contact area I; the ACF 51formed in the ACF deposit area III to sufficiently cover the transparentmetal layer 49; and a TCP layer 53 formed on the ACF 51. Generally, theLCD device further includes a color filter substrate 62 and a sealingcompound 60 for sealing the two substrates (i.e., the substrate 41 andthe color filter substrate). The first metal layer 43 of FIG. 3 is thegate metal connected to a thin film transistor in the active region. Thetransparent metal layer 51 may be made of a transparent conductivematerial, such as, ITO (Indium Tin Oxide), which may be used as a pixelelectrode of the active region.

In the gate pad configured as above, since the transparent metal layer49 and the contact holes transmitting the gate signal inputted from theACF 51 to the first metal layer 43, as well as the first metal layer 43used as the gate metal exist within the ACF 51, there is no danger ofexposing the transparent metal layer 49 or the contact holes to ambientair. Further, since the first metal layer 43 adjacent to the grindingarea II is covered by the gate insulating film 45 and the protectivefilm 47 and the transparent metal layer 49 is covered by the ACF 51,even if all process including a grinding process are finished and anelectrical signal is applied for operation, there are prevented thefirst metal layer 43 and the transparent metal layer 49 from beingaffected by any corrosion and electrolytic corrosion due to a moisture.

To be specific, there is no possibility that the transparent metal layer49 adjacent to the grinding area II and the first metal layer 43 arecorroded due to a moisture, or electrolytically corroded due to anelectrochemical reaction between the metals. Since the transparent metallayer 49 adjacent to the active region and the contact holes existswithin the ACF 51, they will not suffer from corrosion or electrolyticcorrosion as a result of their exposure to ambient air.

A method for manufacturing the gate pad according to the presentinvention will now be explained with reference to FIGS. 4A through 4F.For reference, the pad region and the active region are manufacturedthrough common process. However, a preferred embodiment of the presentinvention will be explained based on the process performed in the padregion.

As depicted in FIG. 4A, the first metal layer 43 acts as the gate metaland is formed on the substrate 41, which is comprised of the activeregion, and the pad region. The pad region is divided into the ACFdeposit area III, the pad contact area I, and the grinding area II.Here, the first metal layer 43 is separated by a predetermined intervalfrom the grinding area II and extends beyond the pad contact area I tothe active region.

Thereafter, the gate insulating film 45 is formed on a front surface ofthe substrate 41 including the first metal layer 43, and the protectivefilm 47 is formed on the gate insulating film 45. A photoresist (notshown) is coated on the protective film 47, and is patterned through anexposure and development process.

As shown in FIG. 4B, the plurality or contact holes 48 are formed withinthe pad contact area I through an engraving process in which thepatterned photoresist is used as a mask. At this time, the thin filmtransistor (not shown) is formed on the active region.

Subsequently, as illustrated in FIG. 4C, the transparent metal layer 49is formed within the pad contact area I to be electrically connected tothe first metal layer 43 through the contact holes 48. Here, thetransparent metal layer 49 is patterned so as to be formed within thepad contact area I. A pixel electrode is formed on the active region andthe transparent metal layer 49 is materialized of the same ITO as theabove pixel electrode. This is because that the active region and thepad region are processed at the same time. If the transparent metallayer 49 is formed at the same time when the pixel electrode of theactive region is formed of the ITO, the process is simplified and anadditional mask is not needed, in comparison with a case that a separatetransparent metal layer is formed. The transparent metal layer 49 doesnot need to be made of the same ITO as the pixel electrode. Instead, thetransparent metal layer 49 can be made of any material having a highelectric conductivity and a high adhesivity to the anisotropicconductive film (ACF).

Next, as shown in FIG. 4D, the gate insulating film 45 and theprotective film 47 in the grinding area II are ground. As shown in FIG.4E, the ACF 51 is formed to entirely cover the pad contact area I. Atthis time, edge portions of the first metal layer 43 contiguous to thegrinding area II are covered by the gate insulating film 45 and theprotective film 47, and the transparent metal layer 49 is covered by theACF 51.

After that, as shown in FIG. 4F, the tape carrier package (TCP) layer 53is formed on an upper part of the ACF 51, thereby completing themanufacturing of the exemplary gate pad according to the presentinvention.

In the method of manufacturing the gate pad according to the presentinvention, since the first metal layer 43 contiguous to the grindingarea II is covered by the gate insulating film 45 and the transparentmetal layer 49 is covered by the ACF 51, there is no danger that theedge portions of the first metal layer 43 and the transparent metallayer 49 would be exposed to ambient air after the grinding process. Inaddition, since the plurality of contact holes 48 within the pad contactarea I and the transparent metal layer 49 contiguous to the activeregion are covered by the ACF 51, edge portions of the contact holes andthe transparent metal layer 49 have no danger of being exposed toambient air.

The data pad according to the present invention will be explained hereinbelow with reference to FIG. 5. FIG. 5 shows a sectional view of thedata pad according to the present invention.

Referring to FIG. 5, the data pad, similarly to the gate pad, generallycomprises an ACF (Anisotropic Conductive Film) deposit area III, a padcontact area I, and a grinding area II. The grinding area II isseparated by a predetermined interval from the pad contact area I. Thepad contact area I is formed within the ACF deposit area III. Here, thepad contact area I includes a plurality of contact holes and atransparent metal layer 49 connected to a first metal layer 43 throughthe contact holes.

To be specific, as depicted in FIG. 5, the data pad comprises asubstrate 41, which includes a pad region (the pad region being dividedinto the grinding area II, the pad contact area I, and the ACF depositarea III, and an active region with a thin film transistor and a pixelelectrode being formed on the active region); a gate insulating film 45formed on the substrate 41; the first metal layer 43 formed on the gateinsulating film over the pad contact area I and the active region; aprotective film 47 laminated on the gate insulating film 45 includingthe first metal layer 43 and having the plurality contact holes throughwhich a surface of the first metal layer 43 is exposed; the transparentmetal layer 49 electrically connected to the first metal layer 43through the contact holes and being formed within the pad contact areaI; an ACF formed on the ACF deposit area III to sufficiently cover thetransparent metal layer 49; and a tape carrier package (TCP) layer 53formed on the ACF 51.

Generally, an LCD further comprises a color filter substrate 62 and asealing compound 60 to bond the two substrates (i.e., the substrate 41and the color filter substrate). The first metal layer 43 may be asource/drain metal formed at the same time as the source/drain electrodeand data wiring in the active region. Further, the transparent metallayer 49 is preferably made of the same material as that of a pixelelectrode of the active region and formed at the same time with thepixel electrode.

In the data pad according to the present invention, since thetransparent metal layer 49 and the contact holes transmit a data signalinputted through the ACF 51 to the first metal layer 43 are formedwithin the ACF 51, the transparent metal layer 49 and the contact holesdo not become exposed. Accordingly, even if all process including agrinding process are completed and an electrical signal is applied foroperation, moisture will not infiltrate into the first metal layer 43contiguous to the grinding area II, which is covered by the protectivefilm 47, or into the transparent metal layer 49, which is covered by theACF 51.

As a result, the transparent metal layer 49 and the first metal layer 43adjacent to the grinding area II will not be corroded due to moistureand will not be electrolytically corroded due to an electrochemicalreaction between the metals. Further, there is no concern that thetransparent metal layer 49 adjacent to the active region and the contactholes are corroded or electrolytically corroded since they are coveredby the ACF 51 so as to be isolated from the outside.

A method for manufacturing the data pad will now be explained withreference to FIGS. 6A through 6F.

Referring to FIG. 6A, the gate insulating film 45 is formed on thesubstrate 41, which includes the active region, and the pad region beingdivided into the ACF deposit area III, the pad contact area I and thegrinding area II. After that, the first metal layer 43 is formed on thegate insulating film 45 to be used as the source/drain metal. Here, thefirst metal layer 43 is distanced by a predetermined interval from thegrinding area II and extends beyond the pad contact area I to the activeregion. The thin film transistor (not shown) is formed on the activeregion. For reference, the metal layer for the gate electrode is formedbefore the gate insulating film 45 is formed. Thereafter, the protectivefilm 47 is formed on a front surface of the substrate 41 including thefirst metal layer 43.

A photoresist (not drawn) is coated on the protective film 47 andpatterned through an exposure and development process. Then, as shown inFIG. 6B, the plurality of contact holes 48 are formed within the padcontact area I through an engraving process using the patternedphotoresist as a mask.

Then, as shown in FIG. 6C, the transparent metal layer 49 is formedwithin the pad contact area I to be electrically connected to the firstmetal layer 43 through the contact holes 48. To be specific, a metalmaterial is formed on a front surface including the contact holes 48,and then the transparent metal layer 49 is patterned to be formed withinthe pad contact area I through a photo-engraving process. Here, thetransparent metal layer 49 is materialized of the same ITO as a materialof the pixel electrode formed in the active region. However, thematerial of the transparent metal layer 49 is not limited to the ITO,rather any material having a high electric conductivity and a highadhesivity to the ACF can be used.

After that, the protective film 47 in the grinding area II is removedthrough the grinding process as shown in FIG. 6D, and the ACF 51 isformed on the ACF deposit area III to sufficiently cover the pad contactarea I as shown in FIG. 6E.

Next, as shown in FIG. 6F, the TCP layer 53 is formed on an upper partof the ACF 51, completing the whole process of manufacturing the datapad according to the present invention. Here, the edge portions of thefirst metal layer 43 and the transparent metal layer 49 are separated bya predetermined interval from the grinding area II thus, the edgeportions of the first metal layer 43 are covered by the protective film47 so that the edge portions of the first metal layer 43 will not beexposed even after completing the grinding process. In addition, theedge portions of the plurality of contact holes 48 and the transparentmetal layer 49 within the pad contact area I are formed within the ACFdeposit area III, thereby preventing the transparent metal layer 49 andthe contact holes 48 from being exposed to ambient air.

As stated above, the LCD pads and the manufacturing method thereofaccording to the present invention have a number of advantages. Forexample, the gate metal and the transparent metal layer in the gate padare prevented from being exposed to ambient air since the gate metaladjacent to the grinding area remain covered by the gate insulating filmand the protective film while the transparent metal layer and thecontact holes within the pad contact area remain covered by the ACF.Thus, electrolytic corrosion due to the electrochemical reaction betweenthe metals and the corrosion due to the moisture are prevented.

In addition, the source/drain metal, the transparent metal layer, andthe contact holes in the data pad are prevented from being exposed sincethe source/drain metal remain covered by the protective film while thetransparent metal layer and the contact holes within the pad contactarea remain covered by the ACF. Thus, electrolytic corrosion due to theelectrochemical reaction between the metals and the corrosion due tomoisture are prevented. As a result, the present invention is capable ofimproving reliability in LCD devices since resistance of the metals ofthe gate pad or the source/drain pad connected to an outside drivingcircuit is not increased due to corrosion or electrolytic corrosion.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the LCD pads of the presentinvention without departing from the spirit or scope of the invention.Thus, it is intended that the present invention cover the modificationsand variations of this invention provided they come within the scope ofthe appended claims and their equivalents.

1. A method for manufacturing a pad structure on a liquid crystaldisplay having a grinding area and a pad contact area, the methodcomprising the steps of: forming gate pads on a substrate separated by adistance from a grinding area defined on the substrate; forming a gateinsulating film on the substrate and the gate pads; forming data pads onthe gate insulating film separated by a distance from the grinding area;forming a protective film on the substrate and the data pads; forming atransparent conductive film to be connected to the gate pads and thedata pads in the pad contact area via contact holes defined in the gateinsulating film and the protective film; forming an anisotropicconductive film on the transparent conductive film to entirely coverupper and side surfaces of the transparent conductive film, wherein theanisotropic conductive film entirely covers the contact holes; and afterthe step of forming the data pad, grinding portions of the gateinsulating film and the protective film disposed in the grinding area toexpose a portion of the substrate in the grinding area; wherein, afterthe grinding step, portions of the gate insulation film and theprotective film remain between the grinding area and side surfaces ofthe data pads.
 2. The method according to claim 1, further comprising astep of forming a tape carrier package layer after the step of formingthe anisotropic conductive film.